k8s集群安装

　　说明：本次安装k8s使用1.20.15版本，docker使用19.03版本，版本依赖参考：https://github.com/kubernetes/kubernetes/blob/v1.20.15/build/dependencies.yaml

　　一、准备机器

192.168.5.200 master
192.168.5.201 node1
192.168.5.202 node2

　　二、关闭防火墙

systemctl stop firewalld
systemctl disable firewalld

　　三、关闭selinux

sed -i 's/enforcing/disabled/' /etc/selinux/config

或者

vi /etc/selinux/config
# 在修改SELINUX=disabled

　　四、关闭swap

swapoff -a  # 临时
sed -ri 's/.*swap.*/#&/' /etc/fstab    # 永久

　　五、修改主机名

hostnamectl set-hostname <hostname>
# 3台机器修改为master/node1/node2

　　六、添加hosts

cat >> /etc/hosts << EOF
192.168.5.200 master
192.168.5.201 node1
192.168.5.202 node2
EOF

　　七、将桥接的IPv4流量传递到iptables的链

cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system

　　八、安装docker-ce（阿里云提供：https://developer.aliyun.com/mirror/docker-ce）

# step 1: 安装必要的一些系统工具
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
# Step 2: 添加软件源信息
sudo yum-config-manager --add-repo https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
# Step 3
sudo sed -i 's+download.docker.com+mirrors.aliyun.com/docker-ce+' /etc/yum.repos.d/docker-ce.repo
# Step 4: 更新并安装Docker-CE
sudo yum makecache fast
sudo yum -y install docker-ce-19.03.15 docker-ce-cli-19.03.15
# Step 4: 开启Docker服务
sudo service docker start

　　九、阿里云镜像加速

sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
  "registry-mirrors": ["https://zo5eqsmr.mirror.aliyuncs.com"]
}
EOF
sudo systemctl daemon-reload
sudo systemctl restart docker

　　十、安装k8s(kubernetes)，教程：https://developer.aliyun.com/mirror/kubernetes

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
setenforce 0
yum install -y kubelet-1.20.15 kubeadm-1.20.15 kubectl-1.20.15
# yum install -y --nogpgcheck kubelet-1.20.15 kubeadm-1.20.15 kubectl-1.20.15 （由于官网未开放同步方式, 可能会有索引gpg检查失败的情况, 这时请用）
systemctl enable kubelet && systemctl start kubelet

　　十一、master执行安装

kubeadm init \
  --apiserver-advertise-address=192.168.5.200 \
  --image-repository=registry.aliyuncs.com/google_containers \
  --kubernetes-version=v1.20.15 \
  --service-cidr=10.96.0.0/12 \
  --pod-network-cidr=10.244.0.0/16

　　等待完成出现：

 　　十二、在其他（node1/node2）节点执行上述图片

kubeadm join 192.168.5.200:6443 --token dpd1wd.sx3eh220tvgsb217 \
    --discovery-token-ca-cert-hash sha256:fa149ffeb30f5b60d790ba4602afaf262ca65de9575534f6563fc8e8ccf3e190

　　十三、使用kubectl工具，查看节点

mkdir -p $HOME/.kubernetes
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kubernetes/config
sudo chown $(id -u):$(id -g) $HOME/.kubernetes/config
$ kubectl get nodes

　　问题：

 　　解决：

vi /etc/profile
#末尾添加 export KUBECONFIG=/etc/kubernetes/admin.conf
source /etc/profile

　　十四、安装kube-flannel

　　1）查看节点状态，全是NotReady

 　　2）问题是因为kube-flannel没有安装

 　　可以看到是因为网络的组件加载一直存在问题，所以需要安装kube-flannel

　　3）下载文件：kube-flannel.yaml，由于FQ的问题，一般是不能下载的。

wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

　　提供文件：kube-flannel.yaml

---
kind: Namespace
apiVersion: v1
metadata:
  name: kube-flannel
  labels:
    pod-security.kubernetes.io/enforce: privileged
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
rules:
- apiGroups:
  - ""
  resources:
  - pods
  verbs:
  - get
- apiGroups:
  - ""
  resources:
  - nodes
  verbs:
  - list
  - watch
- apiGroups:
  - ""
  resources:
  - nodes/status
  verbs:
  - patch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: flannel
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: flannel
subjects:
- kind: ServiceAccount
  name: flannel
  namespace: kube-flannel
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: flannel
  namespace: kube-flannel
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: kube-flannel-cfg
  namespace: kube-flannel
  labels:
    tier: node
    app: flannel
data:
  cni-conf.json: |
    {
      "name": "cbr0",
      "cniVersion": "0.3.1",
      "plugins": [
        {
          "type": "flannel",
          "delegate": {
            "hairpinMode": true,
            "isDefaultGateway": true
          }
        },
        {
          "type": "portmap",
          "capabilities": {
            "portMappings": true
          }
        }
      ]
    }
  net-conf.json: |
    {
      "Network": "10.244.0.0/16",
      "Backend": {
        "Type": "vxlan"
      }
    }
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: kube-flannel-ds
  namespace: kube-flannel
  labels:
    tier: node
    app: flannel
spec:
  selector:
    matchLabels:
      app: flannel
  template:
    metadata:
      labels:
        tier: node
        app: flannel
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: kubernetes.io/os
                operator: In
                values:
                - linux
      hostNetwork: true
      priorityClassName: system-node-critical
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni-plugin
       #image: flannelcni/flannel-cni-plugin:v1.1.0 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel-cni-plugin:v1.1.0
        command:
        - cp
        args:
        - -f
        - /flannel
        - /opt/cni/bin/flannel
        volumeMounts:
        - name: cni-plugin
          mountPath: /opt/cni/bin
      - name: install-cni
       #image: flannelcni/flannel:v0.19.2 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.2
        command:
        - cp
        args:
        - -f
        - /etc/kube-flannel/cni-conf.json
        - /etc/cni/net.d/10-flannel.conflist
        volumeMounts:
        - name: cni
          mountPath: /etc/cni/net.d
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
      containers:
      - name: kube-flannel
       #image: flannelcni/flannel:v0.19.2 for ppc64le and mips64le (dockerhub limitations may apply)
        image: docker.io/rancher/mirrored-flannelcni-flannel:v0.19.2
        command:
        - /opt/bin/flanneld
        args:
        - --ip-masq
        - --kube-subnet-mgr
        resources:
          requests:
            cpu: "100m"
            memory: "50Mi"
          limits:
            cpu: "100m"
            memory: "50Mi"
        securityContext:
          privileged: false
          capabilities:
            add: ["NET_ADMIN", "NET_RAW"]
        env:
        - name: POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        - name: EVENT_QUEUE_DEPTH
          value: "5000"
        volumeMounts:
        - name: run
          mountPath: /run/flannel
        - name: flannel-cfg
          mountPath: /etc/kube-flannel/
        - name: xtables-lock
          mountPath: /run/xtables.lock
      volumes:
      - name: run
        hostPath:
          path: /run/flannel
      - name: cni-plugin
        hostPath:
          path: /opt/cni/bin
      - name: cni
        hostPath:
          path: /etc/cni/net.d
      - name: flannel-cfg
        configMap:
          name: kube-flannel-cfg
      - name: xtables-lock
        hostPath:
          path: /run/xtables.lock
          type: FileOrCreate

　　4）安装

kubectl apply -f kube-flannel.yaml

　　十五、查看节点状态

 　　十六、阿里云镜像中心地址：

　　https://cr.console.aliyun.com/cn-hangzhou/instances/images

　　https://cr.console.aliyun.com/cn-hangzhou/instances/favourites

 　　十七、总结：k8s的本地集群安装方式就可以了，在云上面使用建议直接买k8s的服务。